A great big eye came into view in the murky distance. The Doctor noted its simple lens design and figured it probably couldn't see very well. It had made the effort, though, so that was saying something.
The Doctor pressed his palm against the tentacle clutching him and Rose.
'I TRUSTED YOU WITH MY ENTIRE BROOD, AND YOU DID NOT FAIL ME. TRUST ME NOW TO PUSH YOU SAFELY FROM MY WORLD, AND I WILL NOT FAIL YOU.'
The Doctor swallowed, nervous. If Rose got injured during the process...
'What do we have to do?'
'ONCE IN YOUR WORLD, EXPEL MINE, AND DO NOT FIGHT ME.'
He took in this information, trying to imagine the situation, and memorised it. His thoughts turned serious, demanding.
'How do you know what we need, how to help us? Keep us safe?'
There was a pause as the Broodmother seemed to think on his thoughts.
'YOU ARE NOT THE FIRST AIR BREATHERS I HAVE SEEN.'
The Doctor had thought as much, but her response stirred his curiousity. He wanted to ask more, but he could tell by the finalised nature of her thoughts that she would not reveal more. Still, they couldn't stay down here, and didn't have much choice.
'Let's get this over with. No, hold on.'
Reaching again to Rose, the Doctor told her the Broodmother's instructions, and she nodded her understanding. He could feel her nervousness as well, not knowing what was going to happen.
'We'll do it together.'
Rose nodded again and smiled brilliantly.
'Together.'
The Doctor turned back to that big, nautilus eye, slapping his hand down on the tentacle.
'Right! Off we go, then!'
The tentacle released them, falling away into the distance until it disappeared. A moment later, it reappeared, along with a second one. The Doctor didn't realise they were both different tentacles until one had slipped almost completely past him and he saw the specialised filaments. It bumped up right against him, the tip of the tentacle only a short ways past his feet.
'HOLD ON TIGHT'
No, this wasn't right. The Broodmother couldn't possibly be accounting for all their needs. They couldn't simply be pulled out of the Drowning Dregs! Nitrogen sickness would kill Rose, for one.
'This won't work!'
The bundle of filaments drew near, and the Doctor blinked and turned his head as they began to cluster around his face.
'DO NOT FIGHT. PULL THEM IN.'
The Doctor stared over at the eye incredulously. She wanted him to what? He sucked in a breath and was about to argue when he felt something against his lips and, alarmingly, along the inside of his throat. Instinctively he coughed, but it didn't stop. The Doctor could see the strands extending from his mouth, and his first thought was to grab at them and pull them out, but he stopped himself, suppressing the reflex to gag as best he could. He concentrated on just breathing calmly, and more of the filaments worked their way in as he did so.
Rose was watching him, looking horrified. He nodded at her, hoping she would get on with her own so they could get out of here and he could get these out of his throat as quickly as possible. While he wasn't afraid the Broodmother was going to hurt them, in this case he feared the unknown, as he felt very vulnerable having anything in his lungs that didn't belong there. Then again, he'd gotten used to that, surviving in the Drowning Dregs, hadn't he?
Once the Broodmother had apparently been satisfied with Rose's eventual cooperation, the tentacles began to move, and both of them gripped tightly to their respective rides. They were being pulled through endless muck, and at one point, the tentacles switched directions and began pushing them, up and up. It was all the Doctor could do to hug the tentacle that was forcing him upside-down out of the Dregs with his arms and legs, despite his second thoughts of leaving its safety.
The temperature grew suddenly colder, and the Doctor could now hear water rushing past his popping ears. He must have been holding his breath, as he wasn't taking any in. He hoped Rose was okay.
With a great crash, the Doctor felt the empty bite of air all around him, was almost blinded by the moonlight of the lagoon's night. A great crushing weight hung in his chest, and he gave an almighty cough. Dark muck spilled from his mouth, squeezing past the bundle of filaments that occupied most of his airway, and splashed into the surface of the water below around the stalk of tentacle that held him aloft.
The Doctor pulled in a gasp of air.
It was freezing and unbearably dry. He wanted nothing more than to plunge back into the depths into the safety of the Dregs and breathe back in its warmth, but fear of the water between kept him hanging on. As he exhaled, more muck worked its way out, and he took in another breath. This would all be over soon. Just breathe.
The filaments tasted like fish and looked like slimy spaghetti, the moonlight glinting off the bundle in front of his mouth. As the tickling in his lungs grew worse, the Doctor shook with the sickening feeling, doing his best to stay attached to his pillar of safety in an alien world.
He saw Rose clinging to the other of the Broodmother's tentacles, and he felt sudden anger at himself for subjecting her to such an experience. She looked all right, though. As long as she kept hanging on, they'd both be all right, he assured himself.
Suddenly, the presence inside his lungs ceased, and he could feel the filaments sliding over his tongue, slipping out. Attached to each end was a dark clod of something, and the Doctor realised it had to be muck that had been lining his lungs. Now able to breathe properly, he filled his lungs with the night air, which no longer stung and felt fresh and sweeter than anything he'd ever breathed before.
The Doctor grinned uncontrollably. Oh, this was brilliant. He looked over and tested his voice.
"Rose!"
She was grinning, too, watching him. "Doctor, we're free!"
The Doctor laughed triumphantly, squeezing the tentacle extra hard in thanks. "Freer than birds. Safe and sound!" He looked around them, nothing but a small island in sight. "What now, we swim?"
As if the Broodmother had read his mind--which, he mused, she probably had--the towering duo tentacles began to migrate towards the island. The Doctor and Rose were carried right over the bank, tipped right-side-up, and deposited on solid, dry land. Rose's tentacle pulled away at once, but the Doctor's lingered against his palm.
'THANK YOU, DOCTOR.'